Abstract :
In 1937, Richard Brauer identified the centralizer algebra of transformations commuting with the action of the complex special orthogonal groups SO(2n). Corresponding to the centralizer algebra Ek(2n) = EndSO(2n)(V k) for V = 2n is a set of diagrams. To each diagram d, Brauer associated a linear transformation Φ(d) in Ek(2n) and showed that Ek(2n) is spanned by the transformations Φ(d). In this paper, we first define a product on Dk(2n), the -linear span of the diagrams. Under this product, Dk(2n) becomes an algebra, and Φ extends to an algebra epimorphism. Since Dk(2n) is not associative, we denote by its largest associative quotient. We then show that when k ≤ 2n, the semisimple quotient of is equal to Ek(2n). Next, we prove some facts about the representation theory of Ek(2n). We compute the dimensions of the irreducible Ek(2n)-modules and give some branching rules.